Method and apparatus for protecting wiring and integrated circuit device

ABSTRACT

A method and apparatus for protecting a conductor in an integrated circuit. A protective covering can be disposed over a conductor for a substantial length along the conductor while allowing a portion of the conductor to be exposed. The protective covering can be configured as a tunnel which runs for a substantial length along the conductor and can be operable to prevent the occurrence of electrical shorts during operation of the integrated circuit. According to one embodiment of the invention the integrated circuit can be configured as a micromachined device with active mechanical components exposed to the atmosphere.

CROSS-REFERENCES TO RELATED APPLICATIONS

[0001] Not Applicable

STATEMENT AS TO RIGHTS TO INVENTIONS MADE UNDER FEDERALLY SPONSOREDRESEARCH OR DEVELOPMENT

[0002] Not Applicable

REFERENCE TO A “SEQUENCE LISTING,” A TABLE, OR A COMPUTER PROGRAMLISTING APPENDIX SUBMITTED ON A COMPACT DISK

[0003] Not Applicable

[0004] The following embodiments of the invention relate generally tointegrated circuits. More particularly, these embodiments relate tomicromachined (MEMS) devices.

BACKGROUND

[0005] In integrated circuits, it is common to provide various layers ofmaterial so as to fabricate the integrated circuit. This process iscompleted by depositing a passivation layer so as to protect the earlierdeposited layers of materials. Furthermore, it is common to cap theintegrated circuits with a plastic material to prevent theirdestruction. One type of integrated circuit, however, does not allow forsuch a passivation layer to be applied in view of the fact that theintegrated circuit is comprised of an active mechanical component.

[0006] For example, in the field of micromachined (MEMS) devices, it iscommon to provide an active mechanical component, such as a mirror, thatneeds to be exposed to the atmosphere. In the case of a MEMS device thatis comprised of mirrors, the mirrors need to be capable of receivinglight transmission signals so that these transmission signals can beproperly routed by reflection from the mirrors. Similarly, othercomponents, for example, allow refraction or diffraction of variousoptical signals. These are merely examples, as MEMS devices can becomprised of other active mechanical components. Such MEMS devices makepackaging of the integrated circuit components difficult in view of thefact that a passivation layer cannot be applied to the entire circuitwhen such active mechanical components must be free to move and receivesignals.

[0007] One aspect of fabrication of integrated circuits is thedeposition of material so as to form conductors that carry electricalsignals throughout the integrated circuit. This is normally accomplishedby depositing a conductive material that is suitable for conducting theparticular electrical signal throughout the integrated circuit. One suchconductive material is polysilicon which is conductive for purposes oftransmitting digital signals in integrated circuits. Under normalcircumstances, when a traditional integrated circuit is beingfabricated, such a conductive material would be encapsulated by othermaterials and possibly a passivation layer so as to protect theconducting material from being exposed to extraneous particles whichoften occur as part of the fabrication process. In the manufacture ofMEMS devices, however, the use of such encapsulating materials is notalways possible, because the active mechanical components cannot beencapsulated without destroying their function. Thus, in packaging MEMSdevices, it is sometimes necessary to deposit conductors which areexposed to the atmosphere and as a result can easily be shorted by therandom particles which exist.

[0008] For example, such random particles can occur merely as dirtparticles that exist in the atmosphere in which the integrated circuitis manufactured. Typically, such particles are filtered out of theprocessing environment through the use of stringent filtering controls;however, such filtering does not always catch every particle. Thus, someparticles still make it though the filtering process and are capable ofshorting out exposed conductors.

[0009] More typical, however, is that the manufacturing process itselfresults in fragments of silicon that are not completely removed duringthe various fabrication steps of a MEMS device. For example, thefabrication process is typically accomplished using deposition ofsuccessive layers of material along with intermediate removal ofportions of these layers of material. Where these layers meet, it istypical to get fragments of material from the edges where other materialhas been removed. Silicon is very brittle, and therefore pieces ofsilicon at the edges where the layers of material meet can easily flakeaway resulting in free particles that drift to other portions of thecircuit. These free particles are unintended; however, they are not thatuncommon. Sometimes, these particles are referred to as “stringers”.Furthermore, stringers can result from sacrificial particles that arereleased during the fabrication process yet not entirely removed by astep of that process. For example, sometimes material can be intended tobe etched away, yet merely broken free without removal from theintegrated circuit. Therefore, this can result in the stringer beingfree to migrate to other portions of the circuit.

[0010] As a result of the presence of inherent dirt and stringers, theseparticles can cause the shorting out of a conductor during operation ofthe integrated circuit. MEMS devices are often different from thetypical integrated circuit. Namely, MEMS devices often operate at veryhigh voltages with a high density of exposed conductors in a given unitof the area of the circuit. In contrast, a typical integrated circuit,such as a memory device, often operates at very low voltages withconductors that are insulated from one another. Furthermore, suchtypical insulated integrated circuit devices usually do not have exposedwiring in the density that is common in MEMS devices. As a result, MEMSdevices can be prone to shorting out as a result of the high voltagesthat exist and the proximity of exposed conductors operating at such ahigh potential difference. For example, such voltages can be in thehundreds of volts as compared to the five (5) volt signals, for example,used in some standard integrated circuit memory devices.

[0011] Thus, there is a desire for a technique that would provide areduction in the occurrence of damage to MEMS devices which is broughtabout, for example, by electrical shorting.

SUMMARY

[0012] One embodiment of the invention provides a method and apparatusfor reducing the occurrence of damage caused by extraneous particles inintegrated circuits. According to this embodiment of the invention, asubstrate is provided for a micromachined device; a conductor isprovided as part of the micromachined device for use in conductingelectrical signals during operation of the micromachined device; and, aprotective covering is provided for the conductor so that the conductoris disposed between the substrate and protective covering.

[0013] According to another embodiment of the invention, a micromachinedapparatus can be fabricated comprising a substrate; a bonding pad; aconductor disposed over the substrate; wherein the conductor iselectrically coupled with the bonding pad; an active mechanicalcomponent disposed over the substrate, wherein the active mechanicalcomponent is configured to move relative to the substrate; and aprotective cover disposed over the conductor so that the conductor isdisposed between the protective cover and the substrate.

[0014] According to another embodiment of the invention, a protectivecovering can be configured for a conductor by depositing a layer ofmaterial over the conductor so as to form a tunnel at least partiallyaround the conductor. Thus the majority of the conductor can beprotected from electrical shorts through the use of the tunnel whichcovers the majority length of the conductor.

[0015] According to another embodiment of the invention, a ground ringcan be established about a conductor. Such a ground ring can beaccomplished by electrically coupling a conductive material with thesubstrate of the circuit so as to provide an equipotential material as aprotective cover for the conductor. Thus, for example, the equipotentialsurface can serve to isolate the conductor from stringers which migratethroughout the circuit.

[0016] Further embodiments of the invention will be apparent to those ofordinary skill in the art from a consideration of the followingdescription taken in conjunction with the accompanying drawings, whereincertain methods, apparatuses, and articles of manufacture for practicingthe embodiments of the invention are illustrated. However, it is to beunderstood that the invention is not limited to the details disclosedbut includes all such variations and modifications as fall within thespirit of the invention and the scope of the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017]FIG. 1 is a cross-sectional view of a micromachined deviceaccording to one embodiment of the invention.

[0018]FIG. 2 is a plan view of a micromachined device showing bondingpads and active mechanical components, as well as conductors covered byprotective layers and conductors having exposed material, according toone embodiment of the invention.

[0019]FIG. 3 is a cross-sectional view of an integrated circuit showinga protective layer of material covering more that one conductoraccording to one embodiment of the invention.

[0020]FIG. 4 is a flowchart illustrating a method of providing amicromachined device according to one embodiment of the invention.

[0021]FIG. 5 is a flowchart illustrating a method of providing amicromachined device according to one embodiment of the invention.

[0022]FIG. 6 is a flowchart illustrating a method of providing anintegrated circuit according to one embodiment of the invention.

[0023]FIG. 7 is a flowchart illustrating a method of providing anintegrated circuit according to one embodiment of the invention.

[0024]FIG. 8 is a flowchart illustrating a method of configuring anequipotential barrier over a conductor according to one embodiment ofthe invention.

[0025]FIG. 9 is a cross-sectional view of the manufacturing process ofan integrated circuit according to one embodiment of the invention.

[0026]FIG. 10 is a cross-sectional view of the manufacturing process ofan integrated circuit according to one embodiment of the invention.

[0027]FIG. 11 is a cross-sectional view of the manufacturing process ofan integrated circuit according to one embodiment of the invention.

[0028]FIG. 12 is a cross-sectional view of the manufacturing process ofan integrated circuit according to one embodiment of the invention.

[0029]FIG. 13 is a cross-sectional view of the manufacturing process ofan integrated circuit according to one embodiment of the invention.

[0030]FIG. 14 is a cross-sectional view of the manufacturing process ofan integrated circuit according to one embodiment of the invention.

[0031]FIG. 15 is a cross-sectional view of the manufacturing process ofan integrated circuit according to one embodiment of the invention.

[0032]FIG. 16 is a cross-sectional view of the manufacturing process ofan integrated circuit according to one embodiment of the invention.

[0033]FIG. 17 is a cross-sectional view of the manufacturing process ofan integrated circuit according to one embodiment of the invention.

[0034]FIG. 18 is a cross-sectional view of an integrated circuitillustrating a protective barrier serving as a tunnel in protecting aconductor according to one embodiment of the invention.

DESCRIPTION

[0035]FIG. 1 illustrates a cross-sectional view of an integrated circuitaccording to one embodiment of the invention. FIG. 1 shows amicromachined device 100 having a substrate 140 manufactured, e.g., fromsilicon. In FIG. 1, a nitride layer of material is shown depositeddirectly over the silicon layer 140. This nitride layer serves as anelectrical insulator, while the silicon serves as a conductor.Furthermore, FIG. 1 shows a cross-sectional view of a conductor 120deposited on the nitride layer. This conductor is suitable forconducting electrical signals in the integrated circuit. For example,such conductors are used for conducting electrical signals from abonding pad of the chip to the input of an active mechanical componenton a MEMS device. The cross-sectional view of FIG. 1 also shows aprotective covering 110 erected around the conductor 120. In FIG. 1,this protective covering is fabricated from polysilicon, which serves asan electrical conductor. The active mechanical component ofmicromachined device 100 is shown as block 160 in FIG. 1. For example,this active mechanical component can be a mirror which reflects opticalsignals received from a fiber optic cable. Other active mechanicalcomponents could include but are not limited to, devices which diffractor refract optical signals. The active mechanical component shown inFIG. 1 is shown as being capable of moving through angle theta (θ).Thus, this active component is capable of moving relative to the fixedsubstrate 140 when the integrated circuit is placed in operation. Thedashed lines intersecting in device 160 in FIG. 1 illustrate theposition of the active mechanical component relative to the substrateand the exemplary movement of the active mechanical component shown inFIG. 1. Of course, other movements could be accomplished as well. As oneof ordinary skill in the art would appreciate, the positioning of amirror, for example, can be produced by layering of additional materialbetween the nitride layer 150 and the active mechanical component 160.For purposes of clarity, these layers are not shown in FIG. 1.

[0036] While FIG. 1 illustrates a cross-sectional view of the integratedcircuit, it is understood that the protective covering 110 need notextend along the entire length of conductor 120. Rather the protectivecovering can be configured so as to extend along a substantial portion,such as 50% or more, or even 70%, 90% or 95% of the length of theconductor.

[0037]FIG. 1 also illustrates a ground ring established by theprotective covering 110 and substrate 140. In view of the fact that theprotective covering sits on blocks of conductive material 112 and 116which are electrically coupled with the silicon layer in FIG. 1, anequipotential circuit is established around the conductor 120. Thus, anyfragment of loose material falling on protective cover 110 would beexposed to the ground voltage reference during operation of theintegrated circuit. Furthermore, the only voltage to which the conductorwould be exposed when surrounded by the ground ring would be the groundvoltage. In addition, surrounding a conductor by the ground ring canhelp to reduce the effect of electrical noise, such as electromagneticinterference, on the signal carried by the conductor. FIG. 1 alsoillustrates that the conductor is adjacent material 170. This materialcould be an insulating material (such as silicon dioxide) oralternatively, if the oxide material is released as part of thefabrication process through the use of hydrofluoric acid (HF), forexample, then the material 170 would simply be the atmosphere in whichthe integrated circuit is operating.

[0038]FIG. 2 illustrates a plan view of an integrated circuit whichexemplifies various embodiments of the invention. In FIG. 2, bondingpads 280, 282, 284, and 286 are shown. Bonding pad 280 is electricallycoupled with conductor 220 which in turn is electrically coupled to anactive mechanical device 260. Similarly, bonding pad 282 is electricallycoupled with conductor 222 which in turn is electrically coupled withactive mechanical device 262. Conductor 222 is protected by protectivecovering 210. In addition, bonding pad 284 is coupled to activemechanical device 264 by exposed conductor 224. Similarly, bonding pad286 is coupled to active mechanical device 266 by a protected conductor226. The protective coverings 210 and 214 shown in FIG. 2 illustratealternative ways of configuring a protective covering for a conductor.Namely, the protective covering for conductor 226 illustrates a squaredoff end to the protective covering. In contrast, the protective covering210 illustrates a flared or funneled end to the protective covering 210.This flare is illustrated as the angled portion 212 of the protectivecovering 210 in FIG. 2. By flaring the end of the protective covering,the walls of the protective covering can be extended away from theexposed conductor. Thus, a stringer which lands on the integratedcircuit is less likely to short out the exposed portion of material inview of the fact that it must be long enough to reach the flared walland the exposed conductor. By widening the distance that the stringermust travel between the exposed conductor and the wall of the protectivecovering, the likelihood of shorting the circuit is reduced. Similarly,the height of the protective covering relative to the conductor could beincreased at the end of a protective material layer so as to accomplishthe same purpose in the perpendicular direction. Thus, a generalfunneling of the end of each protective covering would reduce thelikelihood of shorts occurring where the protective covering ends andexposed conductors occur. Alternatively, the protective covering cansimply be squared off as shown by protective covering 214 and thecross-sectional view of FIG. 1. This is perhaps a more straightforwardand easier way to deposit material as a protective covering. FIG. 2, asa plan view, also illustrates that the protective covering can cover asubstantial portion of an exposed conductor. Similarly, FIG. 2illustrates that protective coverings could be fabricated foralternative conductors, rather than all conductors. The conductors shownin FIG. 2 are merely exemplary. It is envisioned that many conductorswill not travel in straight lines directly from a bonding pad to theactive device.

[0039]FIG. 3 illustrates a cross-sectional view of an integrated circuitaccording to another embodiment of the invention. In FIG. 3, aprotective covering 310 is used to cover more than one conductor, namelyconductors 322, 324, and 326. Thus, in FIG. 3 the protective covering310 can be utilized to protect more than one conductor. In the exampleof FIG. 3, a substrate 340 is covered with insulator material 350. Theprotective covering is coupled to the substrate 340 through depositedmaterial 312 and 314. Thus, protective covering material could bepolysilicon which is coupled to a silicon substrate. The insulatormaterial could be nitride or a nitride oxide combination. Theintermediate material which couples the protective covering to thesubstrate could be a polysilicon or metal which can similarly be usedfor the conductors being protected.

[0040]FIG. 4 illustrates a flowchart 400 for implementing a methodaccording to one embodiment of the invention. In block 410, a substrateis provided for a micromachined device. In block 420, a conductor isprovided as part of the micromachined device. In block 430 a protectivecovering is provided for the conductor so that the conductor is disposedbetween the substrate and the protective covering.

[0041] In FIG. 5., flowchart 500 illustrates a method according toanother embodiment of the invention. In block 510, a substrate isprovided for a micromachined device. In block 520, a conductor isprovided as part of the micromachined device. In block 530, a protectivecovering is provided for the conductor so that the conductor is disposedbetween the substrate and the protective covering. In block 540, thesubstrate is electrically coupled with the protective covering. In block550, the protective covering is configured so as to form a tunnel overthe conductor. In block 560, the manufacture of the micromachined deviceis completed without using a passivation layer over the previouslydeposited layers of material.

[0042]FIG. 6 illustrates a flowchart 600 which describes a method ofprotecting a conductor in an integrated circuit according to oneembodiment of the invention. In block 610 of FIG. 6, a substrate isprovided. Block 620 shows that a bonding pad is disposed over thesubstrate, while block 630 shows that a conductor is disposed over thesubstrate with the conductor being electrically coupled with the bondingpad. Block 640 illustrates that an active mechanical component isdisposed over the substrate wherein the active mechanical component isconfigured to move relative to the substrate. In block 650, a protectivecover is disposed over the conductor so that the conductor is disposedbetween the protective covering and the substrate.

[0043]FIG. 7 illustrates a flowchart 700 which describes a methodaccording to another embodiment of the invention. In FIG. 7, block 710shows that a bonding pad is provided as part of a micromachinedapparatus. An active mechanical component is provided and configured tomove during operation of the micromachined apparatus according to block720. In block 730, a conductor is deposited between the activemechanical component and the bonding pad. In block 740, the conductorplaced between the mechanical component and the bonding pad isprotected.

[0044]FIG. 8 illustrates an embodiment of the invention for providing anequipotential barrier for a conductor in an integrated circuit. Namely,in block 810 a substrate is provided. As shown in block 820, a conductoris disposed over the substrate. And, in block 830, an equipotentialbarrier is configured to extend at least partially around the conductor.

[0045] By depositing the protective material so as to cover asubstantial portion of the conductor, the conductor can be protectedfrom electrical shorts without the need for depositing a passivationlayer. Thus, the fabrication of micromachined devices can beaccomplished without the act of depositing a passivation layer ofmaterial over the other previously deposited layers of material used tomanufacture the integrated circuits.

[0046]FIGS. 9 through 18 illustrate the process of fabricating aprotective layer for a conductor according to one embodiment of theinvention. In FIG. 9, a substrate of silicon 900 is shown. On top ofthis layer of silicon, an oxide, such as silicon dioxide 910 is shown ashaving been deposited. Furthermore, a nitride layer 920 is shown ashaving been deposited. The nitride oxide layers form a nitride oxidestack. Thus, the silicon substrate has the property of being anelectrical conductor, whereas the nitride oxide layers serve as anelectrical insulator.

[0047]FIG. 10 illustrates that a mask can be used to create channels1010 and 1020 in the nitride oxide layers. The mask used to accomplishthis is shown at the top of FIG. 10.

[0048]FIG. 11 shows a deposited layer of conducting material 1100. Forexample, in FIG. 11 polysilicon can be used as the electricallyconducting material. This polysilicon layer is deposited over thenitride layer so as to line the channels which were previously formed inFIG. 10.

[0049] In FIG. 12 an etching procedure can take place through the use ofa mask. The mask is shown at the top of FIG. 12. This process removesthe polysilicon layer leaving remnants of the polysilicon layer 1230,1210, and 1220. Segments 1230 and 1220 serve to line the previouslyformed channel while remnant 1210 is configured by the mask to act at aconductor. The polysilicon deposited and etched away is commonlyreferred to as poly0.

[0050]FIG. 13 illustrates the deposition of an insulating layer 1300,e.g., silicon dioxide. The silicon dioxide layer shown in FIG. 13 servesas a sacrificial oxide layer.

[0051]FIG. 14 illustrates that through the use of another mask, thesacrificial oxide layer can be etched away. This is shown in FIG. 14where the sacrificial oxide layer has been etched away immediately abovethe polysilicon segment, but not above the polysilicon conductor.

[0052]FIG. 15 illustrates the deposition of a second polysilicon layer1500. This polysilicon layer is deposited over the previously appliedsacrificial layer in FIG. 15. The polysilicon layer is coupled to thepreviously deposited polysilicon layer which couples the secondpolysilicon layer to the silicon substrate in FIG. 15.

[0053] In FIG. 16, yet another mask is used to etch away the portions ofthe previously applied polysilicon layer. Thus, as shown in FIG. 16, thedeposited polysilicon layer is shown above the conductor, yet removedabove the sacrificial oxide layer.

[0054] In FIG. 17, two additional sacrificial oxide layers are applied.Sacrificial oxide layer 1700 is deposited first, followed by sacrificialoxide layer 1710. As can be seen in the embodiment shown in FIG. 17, thesecond sacrificial oxide layer 1710 is thicker than the firstsacrificial oxide layer 1700. These sacrificial oxide layers can be usedto orient the active mechanical component. After deposition of thesacrificial oxide layers and fabrication of other components of thecircuit, these sacrificial oxide layers can be released, such as throughthe use of hydrofluoric acid. The use of the hydrofluoric acid removesthe oxide layers of material, but does not remove the polysilicon ornitride layers. Thus, as shown in FIG. 18, the removal of thesacrificial oxide layers leaves a conductor 1820 protected by aprotective covering 1810 a. The substrate 1840 is covered by the oxidelayer 1845 and nitride layer 1850 in FIG. 18. The protective covering1810 is electrically coupled with the silicon substrate 1840 by thepoly0 material 1830 and 1832. Thus, the fabrication process allows theformation of a conductor which is at least partially covered with aprotective covering.

[0055] The protective covering can be deposited in a variety of ways,for example, it can be applied as a single layer which in view of thetopology of the underlying layers can form a tunnel around a conductor.Such a tunnel is illustrated in the cross sectional view of FIG. 1. Thistunnel can extend along the length of the conductor. As noted earlier,this tunnel can extend partially around the conductor, yet beelectrically coupled with other electrically conductive material so asto form a ground circuit around the conductor. Thus, this ground circuitwould extend for the length of the tunnel. Furthermore, it is envisionedthat the protective covering could be comprised of more than one type ofmaterial.

[0056] According to one embodiment of the invention, the equipotentialbarrier can be manufactured by utilizing polysilicon as the material forthe equipotential barrier. Furthermore, this polysilicon material can beelectrically coupled with the substrate so as to form an equipotentialring. In addition, the substrate can be electrically coupled with acircuit ground, such as to a bonding pad which is coupled to the circuitground, so as to establish a ground ring about the conductor which isbeing protected.

[0057] The fabrication process has been described as locating layers ofmaterial, e.g., protective covering “over” another layer of material.The word “over” is intended to mean above the referenced layer. Forexample, the substrate layer when the substrate is oriented on asupporting surface. However, it is not required that the two layers besucceeding layers of material. There can be intermediate layers ofmaterial between the two referenced layers. Furthermore, “equipotentialring” is understood to mean that the voltage of the ring relative to areference voltage is substantially equal throughout the ring. It isrecognized that due to the resistive properties of some materials usedin the manufacture of integrated circuit devices, that the voltage willnot be exactly equal throughout the entire ground ring. However, suchnegligible differences introduced by the materials are not considered totake such structures out of the definition of equipotential ring, aswould be understood by one of ordinary skill in the art.

[0058] While various embodiments of the invention have been described asmethods or apparatus for implementing the invention, it should beunderstood that some embodiments can be similarly implemented throughcode coupled to a computer, e.g., code resident on a computer oraccessible by the computer. For example, software and databases could beutilized to implement many of the methods discussed above. Thus, inaddition to embodiments where the invention is accomplished by hardware,it is also noted that these embodiments can be accomplished through theuse of an article of manufacture comprised of a computer usable mediumhaving a computer readable program code embodied therein, which causesthe enablement of the functions disclosed in this description.Therefore, it is desired that embodiments of the invention also beconsidered protected by this patent in their program code means as well.

[0059] It is also noted that many of the structures, materials, and actsrecited herein can be recited as means for performing a function orsteps for performing a function. Therefore, it should be understood thatsuch language is entitled to cover all such structures, materials, oracts disclosed within this specification and their equivalents.

[0060] In addition to embodiments where the invention is accomplished byhardware, it is also noted that these embodiments can be accomplishedthrough the use of an article of manufacture comprised of a computerusable medium having a computer readable program code embodied therein,which causes the enablement of the functions and/or fabrication of thehardware disclosed in this specification. For example, this might beaccomplished through the use of hardware description language (HDL),register transfer language (RTL), VERILOG, VHDL, or similar programmingtools, as one of ordinary skill in the art would understand. It istherefore envisioned that the functions accomplished by the presentinvention as described above could be represented in a core which couldbe utilized in programming code and transformed to hardware as part ofthe production of integrated circuits. Therefore, it is desired that theembodiments expressed above also be considered protected by this patentin their program code means as well.

[0061] It is thought that the embodiments of the present invention andmany of its attendant advantages will be understood from thisspecification and it will be apparent that various changes may be madein the form, construction, and arrangement of the parts thereof withoutdeparting from the spirit and scope of the invention or sacrificing allof its material advantages, the form herein before described beingmerely exemplary embodiments thereof.

1. A method of protecting a conductor in a micromachined device, saidmethod comprising: providing a substrate for a micromachined device;providing a conductor as part of said micromachined device for use inconducting electrical signals during operation of said micromachineddevice; providing a protective covering for said conductor so that saidconductor is disposed between said substrate and said protectivecovering and so that said protective covering is configured so as toform a tunnel relative to said conductor.
 2. The method as described inclaim 1 wherein said protective covering comprises polysilicon.
 3. Themethod as described in claim 1 wherein said providing a protectivecovering comprises depositing said protective covering as a layer ofmaterial.
 4. The method as described in claim 3 wherein said layer ofmaterial protects a plurality of conductors.
 5. The method as describedin claim 1 and further comprising: electrically coupling said protectivecovering with said substrate so as to configure a ground ring aroundsaid conductor.
 6. (Cancelled)
 7. The method as described in claim 1 andfurther comprising: not depositing a passivation layer over an activemechanical component of said micromachined device. 8-14 (cancelled) 15.A method of protecting a conductor in a micromachined device, saidmethod comprising: providing a micromachined device comprising asubstrate; providing a conductor as part of said micromachined device;providing as part of said micromachined device a protective covering,wherein said conductor is disposed between said protective covering andsaid substrate of said micromachined device and wherein said protectivelayer of material is configured so as to form a tunnel relative to saidconductor.
 16. The method as described in claim 15 wherein saidproviding a protective covering comprises utilizing polysilicon as saidprotective covering.
 17. The method as described in claim 15 whereinsaid providing said protective covering comprises depositing saidprotective covering as a layer of material.
 18. The method as describedin claim 17 wherein said layer of material protects a plurality ofconductors.
 19. The method as described in claim 15 and furthercomprising: electrically coupling said protective covering with saidsubstrate so as to configure a ground ring around said conductor. 20.(Cancelled)
 21. The method as described in claim 15 and furthercomprising: not depositing a passivation layer over an active mechanicalcomponent of said micromachined device. 22-31 (cancelled)
 32. A methodof providing a micromachined apparatus, said method comprising:providing a substrate; disposing a bonding pad over said substrate;disposing a conductor over said substrate, wherein said conductor iselectrically coupled with said bonding pad; disposing an activemechanical component over said substrate, wherein said active mechanicalcomponent is configured to move relative to said substrate duringoperation of said micromachined apparatus; disposing a protective coverover said conductor so that said conductor is disposed between saidprotective covering and said substrate and so that said protective coveris configured so as to form a tunnel relative to said conductor.
 33. Themethod as described in claim 32 wherein said active mechanical componentcomprises a mirror.
 34. The method as described in claim 33 wherein saidmirror comprises silicon.
 35. The method as described in claim 32wherein said active mechanical component is exposed to the atmosphereatomosphere during operation of said micromachined apparatus.
 36. Themethod as described in claim 32 wherein a portion of said conductor isexposed to the atmosphere during operation of said micromachinedapparatus.
 37. The method as described in claim 32 wherein saidprotective cover comprises polysilicon.
 38. The method as described inclaim 32 wherein said protective cover is operable so as to protect saidconductor from an electrical short when a voltage of at least 100 Voltsis applied to said protective cover.
 39. The method as described inclaim 32 and further comprising: electrically coupling said protectivecover with said substrate so as to configure a ground ring around saidconductor.
 40. (Cancelled)
 41. The method as described in claim 32 andfurther comprising: not depositing a passivation layer over an activemechanical component of said micromachined apparatus.
 42. A method ofconfiguring a micromachined apparatus, said method comprising: providinga bonding pad as part of said micromachined apparatus; providing anactive mechanical component, wherein said active mechanical component isconfigured to move during operation of said micromachined apparatus;disposing a conductor between said active mechanical component and saidbonding pad; protecting at least a portion of said conductor disposedbetween said active mechanical component and said bonding pad with aprotective layer of material operable to protect said conductor fromelectrical shorts and configured so as to form a tunnel relative to saidconductor.
 43. The method as described in claim 42 wherein saidproviding an active mechanical component comprises providing a mirror.44. The method as described in claim 42 and further comprisingconfiguring said active mechanical component so as to be exposed to theatmosphere during operation of said micromachined apparatus.
 45. Themethod as described in claim 42 wherein said protective layer ofmaterial protects said conductor when a voltage of at least 100 Volts isapplied to said protective layer of material.
 46. The method asdescribed in claim 42 and further comprising: configuring saidprotective layer of material so as to form at least part of a groundring around said conductor.
 47. (cancelled)
 48. The method as describedin claim 42 and further comprising: not depositing a passivation layerover said active mechanical component. 49-55 (cancelled)
 56. A methodcomprising: providing a substrate; disposing a conductor over saidsubstrate operable for conducting electrical signals; configuring anequipotential barrier at least partially around said conductor operablefor protecting said conductor from electrical shorts, wherein saidconfiguring said equipotential barrier comprises: configuring a tunnelof electrically conductive material over said conductor; and couplingsaid electrically conductive material with said substrate.
 57. Themethod as described in claim 56 wherein said configuring anequipotential barrier comprises: depositing polysilicon over saidconductor; and electrically coupling said polysilicon with saidsubstrate so as to form an equipotential ring.
 58. The method asdescribed in claim 57 and further comprising: electrically coupling saidequipotential ring to a circuit ground.
 59. (Cancelled)
 60. The methodas described in claim 59 and further comprising: electrically couplingsaid equipotential barrier to a circuit ground. 61-65 (Cancelled)
 66. Amethod of protecting a conductor in a micromachined device, said methodcomprising: providing a substrate for a micromachined device; providinga conductor as part of said micromachined device for use in conductingelectrical signals during operation of said micromachined device;providing a protective covering for said conductor so that saidconductor is disposed between said substrate and said protectivecovering; electrically coupling said protective covering with saidsubstrate so as to configure a ground ring around said conductor. 67.The method as described in claim 66 wherein said protective coveringcomprises polysilicon.
 68. The method as described in claim 66 whereinsaid providing a protective covering comprises depositing saidprotective covering as a layer of material.
 69. The method as describedin claim 68 wherein said layer of material protects a plurality ofconductors.
 70. The method as described in claim 66 and furthercomprising: not depositing a passivation layer over an active mechanicalcomponent of said micromachined device.
 71. A method of providing amicromachined apparatus, said method comprising: providing a substrate;disposing a bonding pad over said substrate; disposing a conductor oversaid substrate, wherein said conductor is electrically coupled with saidbonding pad; disposing an active mechanical component over saidsubstrate, wherein said active mechanical component is configured tomove relative to said substrate during operation of said micromachinedapparatus; disposing a protective cover over said conductor so that saidconductor is disposed between said protective covering and saidsubstrate; electrically coupling said protective cover with saidsubstrate so as to configure a ground ring around said conductor. 72.The method as described in claim 71 wherein said active mechanicalcomponent comprises a mirror.
 73. The method as described in claim 72wherein said mirror comprises silicon.
 74. The method as described inclaim 71 wherein said active mechanical component is exposed to theatmosphere during operation of said micromachined apparatus.
 75. Themethod as described in claim 71 wherein a portion of said conductor isexposed to the atmosphere during operation of said micromachinedapparatus.
 76. The method as described in claim 71 wherein saidprotective cover comprises polysilicon.
 77. The method as described inclaim 71 wherein said protective cover is operable so as to protect saidconductor from an electrical short when a voltage of at least 100 Voltsis applied to said protective cover.
 78. The method as described inclaim 71 and further comprising: not depositing a passivation layer overan active mechanical component of said micromachined apparatus.
 79. Amethod of configuring a micromachined apparatus, said method comprising:providing a bonding pad as part of said micromachined apparatus;providing an active mechanical component, wherein said active mechanicalcomponent is configured to move during operation of said micromachinedapparatus; disposing a conductor between said active mechanicalcomponent and said bonding pad; protecting at least a portion of saidconductor disposed between said active mechanical component and saidbonding pad with a protective layer of material operable to protect saidconductor from electrical shorts; configuring said protective layer ofmaterial so as to form at least part of a ground ring around saidconductor.
 80. The method as described in claim 79 wherein saidproviding an active mechanical component comprises providing a mirror.81. The method as described in claim 79 and further comprisingconfiguring said active mechanical component so as to be exposed to theatmosphere during operation of said micromachined apparatus.
 82. Themethod as described in claim 79 wherein said protective layer ofmaterial protects said conductor when a voltage of at least 100 Volts isapplied to said protective layer of material.
 83. The method asdescribed in claim 79 and further comprising: not depositing apassivation layer over said active mechanical component.